Mun-hee is so annoyed by Hae-mi who always acts like she knows best and tries to lecture her. As Hae-mi makes her look bad even in front of her own friends, Mun- hee whines about it to Soon-jae. But even Soon-jae says it is her fault and makes Mun-hee cry. Min-jeong decides to take firm measures against her students as they don’t take her seriously.